Twin keel adventures - canards!

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pinhead
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Twin keel adventures - canards!

Post by pinhead » Sun Jan 10, 2021 4:41 pm

I made myself a twin keel fish. 5' 3 1/2" x 19 7/8" x 2.4" about 30 litres (flat deck adds a lot of volume) Glassed on keels. Keels are 6" base x 5" high.
Bottom is a subtle double concaved vee. Low to medium volume HPSB rails

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Ok first couple of surfs on it were perplexing - it would bog and times and then take off like a rocket at others. I thought this was probably due to the fact I'd used a more HPSB tail rocker. Because the fins are at 7" this put curve too far in front of the fins so rail drag in turns and fin lift were tipping back and forth, rather than working together.
I solved this problem by adding small twinzer canards in front of the keels. This bought the fin lift in line with rocker curve and the design was suddenly amazeballs.

I'm keen to keep iterating the design PM me if you want the Shape 3d file - I've updated it to move the tail rocker lift back. If you look at the pic from tulla tub you'll see the lift from the fins + canards is making the board plane in the back third. I think the nose would catch without the canards so I've lifted the nose rocker a pinch so you could run the board with just keels. Although I think the canards make the ride a little more civilised,
Image

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daryl wrote:
Sat Oct 05, 2019 5:43 am
We were waiting to get a donkey until it killed someone

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Trev
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Re: Twin keel adventures - canards!

Post by Trev » Sun Jan 10, 2021 4:59 pm

👍
#sixfeetissixfeet!

Beanpole
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Re: Twin keel adventures - canards!

Post by Beanpole » Sun Jan 10, 2021 5:36 pm

You can definitely see the water squirting out off the canards in the last photo. Nice looking fish.

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steve shearer
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Re: Twin keel adventures - canards!

Post by steve shearer » Sun Jan 10, 2021 5:49 pm

I like the last shot.

but the hull still looks under-powered - ie not attaining the speed necessary to fully engage the canards.
I want Nightclub Dwight dead in his grave I want the nice-nice up in blazes

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pinhead
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Re: Twin keel adventures - canards!

Post by pinhead » Sun Jan 10, 2021 6:27 pm

steve shearer wrote:
Sun Jan 10, 2021 5:49 pm
I like the last shot.

but the hull still looks under-powered - ie not attaining the speed necessary to fully engage the canards.

Yes I'm thinking the vee is exaggerating the problem with the rocker curve in front of the fins. I think flattening the rocker curve slightly will fix that so I'll probably do a version 2 (theres only so much you can do with fins to fix a fundamental problem) I haven't ridden a vee bottom before, it feels buttery smooth going rail to rail though, so I'll keep that.

new rocker:

Image
daryl wrote:
Sat Oct 05, 2019 5:43 am
We were waiting to get a donkey until it killed someone

channels
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Re: Twin keel adventures - canards!

Post by channels » Sun Jan 10, 2021 9:50 pm

Looks good Pinny.
How tall are you?

buddy
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Re: Twin keel adventures - canards!

Post by buddy » Sun Jan 10, 2021 10:02 pm

Nice pinny.
How cool is the pattern of the wave on the last pic with you saying ooooft! into it?

Image

Beanpole
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Re: Twin keel adventures - canards!

Post by Beanpole » Mon Jan 11, 2021 9:11 am

That's because Pinny has just ripped the top off the wave with his canard cutback.
So basically the canards are doing what a normal quad setup on a fish would do more or less?

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pinhead
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Re: Twin keel adventures - canards!

Post by pinhead » Mon Jan 11, 2021 9:22 am

I'm 175 cm. Most people will tell you canards direct water flow around the big fins. I think on a surfboard they do that but also move the fin engagement forward slightly and tame a twitchy twin by extending the turn side base.

This board feels nothing like a quad BTW
daryl wrote:
Sat Oct 05, 2019 5:43 am
We were waiting to get a donkey until it killed someone

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pinhead
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Re: Twin keel adventures - canards!

Post by pinhead » Mon Jan 11, 2021 10:33 am

buddy wrote:
Sun Jan 10, 2021 10:02 pm
Nice pinny.
How cool is the pattern of the wave on the last pic with you saying ooooft! into it?
People could hear me saying "ooooft" from the shore
daryl wrote:
Sat Oct 05, 2019 5:43 am
We were waiting to get a donkey until it killed someone

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